Non-minimal Coupling Branes

TL;DR

This paper explores thick braneworld models with non-minimal scalar coupling, presenting analytic solutions, analyzing stability, and confirming the localization of gravity, thus supporting the recovery of Newtonian gravity in four dimensions.

Contribution

It provides new analytic solutions for non-minimally coupled thick branes and analyzes their stability and gravity localization properties.

Findings

Two categories of brane configurations identified: standard and deformed.

No tachyonic instabilities found in metric perturbations.

Gravity zero mode is localized, enabling Newtonian potential recovery.

Abstract

We study a thick and Z_2 symmetric braneworld model with a non-minimally coupled bulk scalar. Several analytic solutions are found. There are two categories of the brane configuration: standard branes and deformed ones. The former is just the same with the solutions in general relativity, whereas the latter has negative effective energy densities in the location of the branes. The question of stability under metric tensor perturbation is also investigated, and there is no tachyon. We show that the gravity zero mode (namely the 4D massless graviton) is the only one state that can be localized on the branes. So Newtonian potential can be recovered in 4D space-time.